<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<!--1,1,2,3,5,8,13,21...-->
<!--这个数字前两位是1，从第三位开始，每一项都是前两位的和-->
<script>
    function fbnq(n){
        if(n == 1 || n == 2){
            return 1;
        }else{
            return fbnq(n-1) + fbnq(n-2)
        }
    }

    console.log(fbnq(25));
</script>
</body>
</html>